Gonadotropin Uptake in Genetic and Irradiation Models of Ovarian Tumorigenesis’

Genetic and irradiation models of ovarian tumorigenesis were investigated for evidence that elevated gonado-tropins have a role in tumorigenesis. WX/W) mice lack oocytes at birth, develop complex mesothelial adenomas by 6 mo, and additional ovarian tumor types later. Uptake of iodinated human chorionic gonadotropin (125J hCG) was measured in mice aged I to 30 mo, and uptake iodinated human follicle-stimulating hormone (1’25J hFSH) was measured in mice aged 1 to 12 mo. Gonadotropin uptake by W/W. ’ ovaries in vivo declined quickly and was undetectable by 6 mo. Irradiated ovaries rapidly lost oocytes and follicular structures, formed meso-thelial adenomas by 5 mo, and later formed additional types of ovarian tumors. In the irradiation model, 125J. hCG uptake also declined quickly and was undetectable by 3 mo of age. Neither the surface nor the tubular epithelium of the mesothelial adenoma were consistently labeled by ‘251-hCG in autoradiography studies with either model. Although these data do not exclude an acute role for gonad otropins in initiation of preneoplastic events, they do indicate that ovarian cells do not require chronic gonadotropin stimulation during subsequent tumorigenesis. These findings are discussed in relation to additional models of ovarian tumorigenesis